Gaming machines, such as slot machines, video poker machines, and the like, have been a cornerstone of the gaming industry for several years. The electronics of a gaming machine typically include a backplane which provides connectors for connection to various devices of the gaming machine, a logic circuit board which includes a central processing unit, memory, and other logic circuitry, and an I/O circuit board which includes communications and power interfaces to devices of the gaming machine. In one arrangement, the logic circuit board and the I/O circuit board are “piggybacked” to the backplane via separate connectors, and are thus disposed parallel to one another. However, the communications interfaces of the I/O circuit board may also include logic circuitry, so the connector connecting the I/O circuit board to the backplane may carry both low-power digital signals and high-power analog signals. The mixing of digital and high-power signals may cause undesirable crosstalk.
To mitigate crosstalk, the digital and high-power signals from the I/O circuit board are connected to pins on the connector such that a digital signal and a high-power signal are not presented to consecutive pins of the connector. This arrangement imposes design challenges as it is often convenient and intuitive to provide digital and high power signals to consecutive pins on the connector.
In addition, the piggybacking of the logic circuit board and the I/O circuit board may create an undesired electromagnetic coupling between the two boards, which can adversely affect signal integrity as the high-current traces create EM fields that radiate away from the I/O circuit board. Moreover, the backplane is connected to the logic circuit board and the I/O circuit board in a perpendicular relationship, further potentially causing undesired electromagnetic coupling between the backplane and the logic circuit board and the I/O circuit board.
A solution is needed, therefore, to address the foregoing disadvantages.